Results 21 to 30 of about 6,655 (246)
On Jensen's functional equation
Aequationes Mathematicae, 1992 The following is offered as main result. Let \((G,\cdot)\) and \((H,+)\) be abelian groups, and \(e\) the neutral element of \((G,\cdot)\). The solutions \(f: G\to H\) of \(f(xy)+f(xy^{-1})=2f(x)\), \(f(e)=0\) are exactly the homomorphisms of \(G\to H\) if, and only if, either \(H\) has no element of order 2 or \([G:G^ 2]\leq 2\), where \(G^ 2:=\{x^ 2 ...
Vasudeva, H.L., Parnami, J.C.
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Stability of Quadratic Functional Equations via the Fixed Point and Direct Method
Journal of Inequalities and Applications, 2010 Cădariu and Radu applied the fixed point theorem to prove the stability theorem of Cauchy and Jensen functional equations. In this paper, we prove the generalized Hyers-Ulam stability via the fixed point method and investigate new theorems via ...
Juri Lee, Eunyoung Son, Hark-Mahn Kim
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Generalized Jensen functional equation on restricted domain
Annals of the West University of Timisoara: Mathematics and Computer Science, 2014 We prove the Hyers-Ulam stability on restricted domains of generalized Jensen functional ...
Chahbi Abdellatif +3 more
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On the stability of generalized d′Alembert and Jensen functional equations [PDF]
International Journal of Mathematics and Mathematical Sciences, 2006 The aim of this paper is to study the stability problem of the generalized d′Alembert, Wilson, and Jensen functional equations.
Kyung Hui Kim, Sever Silvestru Dragomir
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A Fixed Point Approach to the Stability of a Functional Equation of the Spiral of Theodorus
Fixed Point Theory and Applications, 2008 Cădariu and Radu applied the fixed point method to the investigation of Cauchy and Jensen functional equations. In this paper, we adopt the idea of Cădariu and Radu to prove the stability of a functional equation of the spiral of Theodorus, f(x+1)=(
John Michael Rassias, Soon-Mo Jung
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On the Intuitionistic Fuzzy Stability of Ring Homomorphism and Ring Derivation
Abstract and Applied Analysis, 2013 We take into account the stability of ring homomorphism and ring derivation in intuitionistic fuzzy Banach algebra associated with the Jensen functional equation.
Jaiok Roh, Ick-Soon Chang
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International Journal of Analysis and Applications, 2019 In this paper, we prove the generalized Hyers-Ulam-Rassias stability of the bi-Cauchy-Jensen functional equation and the bi-additive-quadratic functional equation in paranormed spaces.
Prondanai Kaskasem, Chakkrid Klin-eam
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Hyperstability of Cauchy–Jensen functional equations
Indagationes Mathematicae, 2016 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
EL-Fassi, Iz-iddine +2 more
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Fuzzy Stability of Jensen‐Type Quadratic Functional Equations [PDF]
Abstract and Applied Analysis, 2009 We prove the generalized Hyers‐Ulam stability of the following quadratic functional equations 2f((x + y)/2) + 2f((x − y)/2) = f(x) + f(y) and f(ax + ay) + (ax − ay) = 2a2f(x) + 2a2f(y) in fuzzy Banach spaces for a nonzero real number a with a ≠ ±1/2.
Jang, Sun-Young +3 more
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Approximate multi-Jensen-cubic mappings and a fixed point theorem
Annales Universitatis Paedagogicae Cracoviensis: Studia Mathematica, 2020 In this paper, we introduce multi-Jensen-cubic mappings and unify the system of functional equations defining the multi-Jensen-cubic mapping to a single equation.
Elahe Ramzanpour, Abasalt Bodaghi
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